Method of preserving perishable goods.



LOUIS PRENZLAU, OF HAMBURG, GERMANY.

METHOD OF PRESERVING PERISHABLE GOODS.

No Drawing.

Specification of Letters Patent.

Application filed July 11, 1910. Serial No. 571,384.

Patented Nov. 26, 1912.

To all whom it may concern:

Be it known that I, Lonrs PRENZLAU, a subject of the German Emperor, andresident of Hamburg, Germany, have invented a certain new and usefulImprovement in Methods of Preserving Perishable Goods, of which thefollowing is a specification.

In methods hitherto employed for preserving eggs a number ofdisadvantages have been present. These consisted mainly in thecomparatively complicated apparatus employed and in the time occupied.In addition lmown methods are not satisfactory when the eggs are to bekept for several months in warm climates. Methods for preserving eggsare known for instance in which the latter are subjected to theimpregnating action of acid vapors under high temperature or pressure oreven in avacuum. Complicated and special apparatus are required and aconsiderable time occupied and in addition, the eggs require to beremoved from the apparatus at the conclusion of the process and packedready for transport, this operation resulting in the breakage of many ofthe eggs. Known methods also in which the eggs are dipped in apreserving material or inserted in packing material impregnated withsubstances containing carbonic acid are of little use when the eggsreach very warm climates. It has now been discovered that the vapors offormaldehyde which are very useful for preserving meat and otherperishable food stuffs, the vapors being forced under pressure into thepores of the meat, are capable of use also for preserving eggs so thateggs subjected to formaldehyde vapor may be kept for any length of timeand even after being kept for a long time in tropical zones are stillpalatable. Owing to the great sensitiveness of eggs to pressure however,it has hitherto been impossible to employ without modification thismethod of preserving eggs as the shells would collapse when theformaldehyde vapors were forced into the same. Therefore the eggsrequire to be subjected to a slight but sufficiently intensive action ofthe formaldehyde vapors.

According to the present invention the packing material which is formedfrom excelsior, shavings or the like is saturated with formaldehyde inthe form of a solution, and the infusorial earth, peat asbestos or thelike used as a filling material is also subjected to the action of theformaldehyde, so that eggs packed in this manner while being packed andduring transport are subjected to the formaldehyde vapors exuding fromthe packing materials.

The modas opemmch is as follows :In the packing case for the eggs whichis of the usual type is inserted the excelsior or the like, which hasbeen previously saturated with formaldehyde. A layer of eggs is nextinserted. While the eggs are being inserted the vapor from theformaldehyde enters the pores in the shells and destroys any bacteriatherein. The eggs are not injured as this formaldehyde is used only in asolution of from 30 to 50%. The filling material now spread on the eggsforms an outer protecting cover also saturated with formaldehyde,preventing the entrance of germs from the atmosphere and preventing theeggs from decomposing. The formaldehyde vapors deposit on the walls ofthe packing case, crystallize there and thus fill the pores of the woodso that formaldehyde cannot escape to a great extent from the case. Inthis manner eggs may be preserved in tropical climates for a period oftwo months or more and will remain perfectly fresh. The eggs preservedin this way do not crack, the albumen does not separate from the yolkand the appearance and flavor are not affected as in previously knownmethods.

Having now described my invention what I claim and desire to secure byLetters Patent of the United States is A method of preserving eggs bypacking them in cases, said method consisting in placing the eggs in thecase in a packing of excelsior saturated with formaldehyde, shutting offthe atmosphere from the egg by filling the pores of the shell withvapors from the formaldehyde, and depositing crystals of said vapor inthe pores of the case.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

LOUIS PRENZLAU.

Witnesses:

GUSTAV WEBER, ERNEST H. L. MUMMENHOFF.

copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

